Vibration devices are used for many various purposes. For example, in a portable telephone terminal, a vibration device is used as means for notifying an incoming call or e-mail, or for notifying a specific time, and the like. In conditions where it is not suitable to emit a sound, a vibration device is in a silent mode of the portable telephone terminal to cause the user to recognize notification such as described above by way of cenesthesia instead of hearing.
Currently, vibration devices that are used for portable telephone terminals create a very small vibration. Therefore, as long as the pocket in which the portable telephone terminal is placed is near the body of the user, it is easy for the user to feel the vibration, however, when the portable telephone terminal is placed in the pocket of a coat or thick clothing, the vibration is absorbed by the cloth and becomes difficult for the user to feel.
Moreover, depending on the site on the body where the vibration is transmitted, the vibration may be difficult to feel. Furthermore, there are differences among individuals of how well the vibration is felt, and for a user that cannot easily feel the vibration, notification by a current vibration device may not be useful.